Pen



FIG. 1 is a top, front, right side perspective view of the pen;

FIG. 2 is a top plan view thereof, shown at an enlarged scale;

FIG. 3 is a bottom plan view thereof, shown at an enlarged scale;

FIG. 4 is a front elevation view thereof,

FIG. 5 is a rear elevation view thereof, and,

FIG. 6 is a left side elevation view thereof, the right side elevation view being a mirror image.

In the drawings, the broken lines are for the purpose of illustrating environment only, and form no part of the claimed design. 

CLAIM The ornamental design for a pen, as shown and described. 